P06FC
Glow Plug Control Module 2 to PCM Communication Circuit
Glow Plug Control Module 2 to PCM Communication Circuit: an electrical fault is present in the circuit. This affects diesel cold-start preheating.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: medium
Symptoms
- Glow plug warning light on (often orange coil symbol)
- Hard cold start or no start in cold weather
- White smoke from exhaust during warm-up
Common causes
Ordered by how often each turns out to be the cause.
- Open or short on communication wireCommon
- Gateway module routing CAN messages incorrectlyLess likely
- CAN terminating resistor (120 Ω) drifted out of specLess likely
Parts involved
- Glow Plug Control Module 2
P06FC is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.